The phrase "chows down" is informal slang for eating heartily or consuming food in large quantities. Its antonyms would be words that describe the opposite of this action, such as fasting, dieting, abstaining, or refraining. These terms indicate a deliberate decision to restrict or reduce one's intake of food for health, religious, or personal reasons. Other antonyms could include words that connote consuming food slowly or in moderation, like nibbling, snacking, savoring, or tasting. Thus, while "chowing down" suggests an indulgent attitude towards food, its antonyms imply a more restrained or disciplined approach.